From a2245f8ff146629159d8c52d60713a262fa1b69a Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Sun, 31 Mar 2019 15:58:54 +0200
Subject: Threaded IO: read side WIP 2.

---
 src/networking.c | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/src/networking.c b/src/networking.c
index fd4e990f4..7d8470489 100644
--- a/src/networking.c
+++ b/src/networking.c
@@ -2496,13 +2496,16 @@ int processEventsWhileBlocked(void) {
 
 int tio_debug = 0;
 
-#define SERVER_MAX_IO_THREADS 32
+#define IO_THREADS_MAX_NUM 128
+#define IO_THREADS_OP_READ 0
+#define IO_THREADS_OP_WRITE 1
 
-pthread_t io_threads[SERVER_MAX_IO_THREADS];
-pthread_mutex_t io_threads_mutex[SERVER_MAX_IO_THREADS];
-_Atomic unsigned long io_threads_pending[SERVER_MAX_IO_THREADS];
-int io_threads_active;
-list *io_threads_list[SERVER_MAX_IO_THREADS];
+pthread_t io_threads[IO_THREADS_MAX_NUM];
+pthread_mutex_t io_threads_mutex[IO_THREADS_MAX_NUM];
+_Atomic unsigned long io_threads_pending[IO_THREADS_MAX_NUM];
+int io_threads_active;  /* Are the threads currently spinning waiting I/O? */
+int io_threads_op;      /* IO_THREADS_OP_WRITE or IO_THREADS_OP_READ. */
+list *io_threads_list[IO_THREADS_MAX_NUM];
 
 void *IOThreadMain(void *myid) {
     /* The ID is the thread number (from 0 to server.iothreads_num-1), and is
@@ -2533,7 +2536,11 @@ void *IOThreadMain(void *myid) {
         listRewind(io_threads_list[id],&li);
         while((ln = listNext(&li))) {
             client *c = listNodeValue(ln);
-            writeToClient(c->fd,c,0);
+            if (io_threads_op == IO_THREADS_OP_WRITE) {
+                writeToClient(c->fd,c,0);
+            } else {
+                readQueryFromClient(NULL,c->fd,c,0);
+            }
         }
         listEmpty(io_threads_list[id]);
         io_threads_pending[id] = 0;
@@ -2550,6 +2557,12 @@ void initThreadedIO(void) {
      * we'll handle I/O directly from the main thread. */
     if (server.io_threads_num == 1) return;
 
+    if (server.io_threads_num > IO_THREADS_MAX_NUM) {
+        serverLog(LL_WARNING,"Fatal: too many I/O threads configured. "
+                             "The maximum number is %d.", IO_THREADS_MAX_NUM);
+        exit(1);
+    }
+
     /* Spawn the I/O threads. */
     for (int i = 0; i < server.io_threads_num; i++) {
         pthread_t tid;
@@ -2684,3 +2697,6 @@ int postponeClientRead(client *c) {
         return 0;
     }
 }
+
+int handleClientsWithPendingReadsUsingThreads(void) {
+}
-- 
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